Outdoor navigation is widely deployed thanks to the development of various global-navigation-satellite-systems (GNSS), e.g., Global Positioning System (GPS), GALILEO, and the like.
Recently, there has been a lot of focus on indoor navigation. This field differs from the filed of outdoor navigation, since the indoor environment does not enable the reception of signals from GNSS satellites. As a result, a lot of effort is being directed towards solving the indoor navigation problem. This problem does not yet have a scalable solution with satisfactory precision.
One solution for indoor navigation includes a Time-of-Flight (ToF) or Round Time Trip (RTT) measurement method. The ToF may be defined as the overall time a signal propagates from a first station, e.g., a user (“client”) mobile device, to a second station, e.g., an access point (AP), and back to the first station. A distance between the first and second stations may be calculated based on the ToF value, for example, by dividing the ToF value by two and multiplying the result by the speed of light.
The first station may determine a relative location of the first station with respect to the second station based on the calculated distance.
An estimated location of the first station may be determined by calculating two or more distances between the first station and two or more other stations, e.g., other APs, and determining the estimated location based on the distances by utilizing a suitable method, e.g., a trilateration method.